In such a gas exchange valve train that is generally also called a “sliding cam valve train,” for error-free engine operation it is basically necessary that the cam lift instantaneously transferred to the gas exchange valve corresponds to the desired value as part of all of the instantaneously set operating parameters and consequently matches the instantaneous axial position of the cam part with its desired position. To be able to correct, if necessary, a defective actual axial position, until now the cam part position has been detected and this position is then compared with the desired axial position in the engine control module. The position detection is performed by evaluating sensor signals that actuate the actuator pin or pins in interaction with the connecting link path. As is provided, for example, in DE 10 2010 035 185 A1 and DE 10 2010 012 470 A1, the cam part can be constructed in the area of the connecting link path so that each axial position can be uniquely identified by a characteristic current signal profile. This also applies to DE 10 2011 004 912 A1 from which it is known to detect a position of the cam part in a sliding cam valve train of the type noted above.